/*-
 * Copyright (c) 1990, 1993, 1994
 *  The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by the University of
 *  California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *  @(#)db.h    8.7 (Berkeley) 6/16/94
 * $FreeBSD: src/include/db.h,v 1.5 2002/03/26 01:35:05 bde Exp $
 */

#ifndef _DB_H_
#define _DB_H_

#include <sys/cdefs.h>

#include <limits.h>

#define RET_ERROR   -1      /* Return values. */
#define RET_SUCCESS  0
#define RET_SPECIAL  1

#define MAX_PAGE_NUMBER 0xffffffff  /* >= # of pages in a file */
typedef __uint32_t  pgno_t;
#define MAX_PAGE_OFFSET 65535       /* >= # of bytes in a page */
typedef __uint16_t  indx_t;
#define MAX_REC_NUMBER  0xffffffff  /* >= # of records in a tree */
typedef __uint32_t  recno_t;

/* Key/data structure -- a Data-Base Thang. */
typedef struct {
    void    *data;          /* data */
    size_t   size;          /* data length */
} DBT;

/* Routine flags. */
#define R_CURSOR    1       /* del, put, seq */
#define __R_UNUSED  2       /* UNUSED */
#define R_FIRST     3       /* seq */
#define R_IAFTER    4       /* put (RECNO) */
#define R_IBEFORE   5       /* put (RECNO) */
#define R_LAST      6       /* seq (BTREE, RECNO) */
#define R_NEXT      7       /* seq */
#define R_NOOVERWRITE   8       /* put */
#define R_PREV      9       /* seq (BTREE, RECNO) */
#define R_SETCURSOR 10      /* put (RECNO) */
#define R_RECNOSYNC 11      /* sync (RECNO) */

typedef enum { DB_BTREE, DB_HASH, DB_RECNO } DBTYPE;

/*
 * !!!
 * The following flags are included in the dbopen(3) call as part of the
 * open(2) flags.  In order to avoid conflicts with the open flags, start
 * at the top of the 16 or 32-bit number space and work our way down.  If
 * the open flags were significantly expanded in the future, it could be
 * a problem.  Wish I'd left another flags word in the dbopen call.
 *
 * !!!
 * None of this stuff is implemented yet.  The only reason that it's here
 * is so that the access methods can skip copying the key/data pair when
 * the DB_LOCK flag isn't set.
 */
#if UINT_MAX > 65535
#define DB_LOCK     0x20000000  /* Do locking. */
#define DB_SHMEM    0x40000000  /* Use shared memory. */
#define DB_TXN      0x80000000  /* Do transactions. */
#else
#define DB_LOCK         0x2000  /* Do locking. */
#define DB_SHMEM        0x4000  /* Use shared memory. */
#define DB_TXN          0x8000  /* Do transactions. */
#endif

/* Access method description structure. */
typedef struct __db {
    DBTYPE type;            /* Underlying db type. */
    int (*close)(struct __db *);
    int (*del)(const struct __db *, const DBT *, u_int);
    int (*get)(const struct __db *, const DBT *, DBT *, u_int);
    int (*put)(const struct __db *, DBT *, const DBT *, u_int);
    int (*seq)(const struct __db *, DBT *, DBT *, u_int);
    int (*sync)(const struct __db *, u_int);
    void *internal;         /* Access method private. */
    int (*fd)(const struct __db *);
} DB;

#define BTREEMAGIC  0x053162
#define BTREEVERSION    3

/* Structure used to pass parameters to the btree routines. */
typedef struct {
#define R_DUP       0x01    /* duplicate keys */
    u_long  flags;
    u_int   cachesize;  /* bytes to cache */
    int maxkeypage; /* maximum keys per page */
    int minkeypage; /* minimum keys per page */
    u_int   psize;      /* page size */
    int (*compare)  /* comparison function */
        (const DBT *, const DBT *);
    size_t  (*prefix)   /* prefix function */
        (const DBT *, const DBT *);
    int lorder;     /* byte order */
} BTREEINFO;

#define HASHMAGIC   0x061561
#define HASHVERSION 2

/* Structure used to pass parameters to the hashing routines. */
typedef struct {
    u_int   bsize;      /* bucket size */
    u_int   ffactor;    /* fill factor */
    u_int   nelem;      /* number of elements */
    u_int   cachesize;  /* bytes to cache */
    __uint32_t      /* hash function */
        (*hash)(const void *, size_t);
    int lorder;     /* byte order */
} HASHINFO;

/* Structure used to pass parameters to the record routines. */
typedef struct {
#define R_FIXEDLEN  0x01    /* fixed-length records */
#define R_NOKEY     0x02    /* key not required */
#define R_SNAPSHOT  0x04    /* snapshot the input */
    u_long  flags;
    u_int   cachesize;  /* bytes to cache */
    u_int   psize;      /* page size */
    int lorder;     /* byte order */
    size_t  reclen;     /* record length (fixed-length records) */
    u_char  bval;       /* delimiting byte (variable-length records */
    char    *bfname;    /* btree file name */
} RECNOINFO;

/*
 * Little endian <==> big endian 32-bit swap macros.
 *  M_32_SWAP   swap a memory location
 *  P_32_SWAP   swap a referenced memory location
 *  P_32_COPY   swap from one location to another
 */
#define M_32_SWAP(a) {                          \
    __uint32_t _tmp = a;                        \
    ((char *)&a)[0] = ((char *)&_tmp)[3];               \
    ((char *)&a)[1] = ((char *)&_tmp)[2];               \
    ((char *)&a)[2] = ((char *)&_tmp)[1];               \
    ((char *)&a)[3] = ((char *)&_tmp)[0];               \
}
#define P_32_SWAP(a) {                          \
    __uint32_t _tmp = *(__uint32_t *)a;             \
    ((char *)a)[0] = ((char *)&_tmp)[3];                \
    ((char *)a)[1] = ((char *)&_tmp)[2];                \
    ((char *)a)[2] = ((char *)&_tmp)[1];                \
    ((char *)a)[3] = ((char *)&_tmp)[0];                \
}
#define P_32_COPY(a, b) {                       \
    ((char *)&(b))[0] = ((char *)&(a))[3];              \
    ((char *)&(b))[1] = ((char *)&(a))[2];              \
    ((char *)&(b))[2] = ((char *)&(a))[1];              \
    ((char *)&(b))[3] = ((char *)&(a))[0];              \
}

/*
 * Little endian <==> big endian 16-bit swap macros.
 *  M_16_SWAP   swap a memory location
 *  P_16_SWAP   swap a referenced memory location
 *  P_16_COPY   swap from one location to another
 */
#define M_16_SWAP(a) {                          \
    __uint16_t _tmp = a;                        \
    ((char *)&a)[0] = ((char *)&_tmp)[1];               \
    ((char *)&a)[1] = ((char *)&_tmp)[0];               \
}
#define P_16_SWAP(a) {                          \
    __uint16_t _tmp = *(__uint16_t *)a;             \
    ((char *)a)[0] = ((char *)&_tmp)[1];                \
    ((char *)a)[1] = ((char *)&_tmp)[0];                \
}
#define P_16_COPY(a, b) {                       \
    ((char *)&(b))[0] = ((char *)&(a))[1];              \
    ((char *)&(b))[1] = ((char *)&(a))[0];              \
}

__BEGIN_DECLS
DB *dbopen(const char *, int, int, DBTYPE, const void *);

#ifdef __DBINTERFACE_PRIVATE
DB  *__bt_open(const char *, int, int, const BTREEINFO *, int);
DB  *__hash_open(const char *, int, int, int, const HASHINFO *);
DB  *__rec_open(const char *, int, int, const RECNOINFO *, int);
void     __dbpanic(DB *dbp);
#endif
__END_DECLS
#endif /* !_DB_H_ */
